On Thursday, oil company ConocoPhillips, power producer NRG Energy, and GE Capital announced they had formed a $300 million joint venture to “accelerate emerging energy technology.”

Obviously, this was in the works long before Obama’s State of the Union address on Tuesday. But it is an indication that even corporations with vested interests in the existing energy infrastructure are hedging their bets.

The new endeavor, called Energy Technology Ventures, plans to distribute the $300 million over the next four years to 30 startups.

But it won’t all go to green energy.

“Energy Technology Ventures will invest in, and offer commercial collaboration opportunities to, venture- and growth-stage energy technology companies in the renewable power generation, smart grid, energy efficiency, oil, natural gas, coal and nuclear energy, emission controls, water and biofuels sectors, primarily in North America, Europe, and Israel,” the three corporate investors said in a statement.

Take the joint venture’s first round of investments, for instance.

Among them is Alta Devices, a secretive solar startup backed by some of Silicon Valley’s most prominent venture capitalists. Alta Devices is “improving the production economics of advanced materials for high-efficiency, low-cost solar energy,” according to Energy Technology Ventures.

The joint venture is also putting money into CoolPlanetBioFuels, a Southern California startup, that has created what it calls “biomass fractionator” to turn woodchips, algae, and crop waste into biofuels. The company says it will package the processor into shipping containers that presumably can be transported to the fuel source. Each processor is expected to produce up to a million gallons of fuel a year, the company says.

The third investment Energy Technology Ventures is revealing probably will raise the hackles of some environmentalists. Ciris Energy, a Colorado company, is “developing technology to biochemically convert coal to methane at large scale and low cost,” according to the investors.

That’s all the information available, as the company’s site offers only generalities about its plans and technology.

For NRG Energy, the new joint venture is just the latest push in a strategy to embrace renewable energy.

Over the past few years the New Jersey power producer, which maintains a portfolio of coal, natural gas, and nuclear power plants, has made big investments in solar and wind energy. For example, it’s putting $300 million into BrightSource Energy’s Ivanpah solar power plant now under construction in the Southern California desert.

NRG is also the main backer of an effort to build a private electric car infrastructure in Houston.

GE, of course, has also made big bets on renewable energy and is the United States’ largest wind turbine manufacturer.

ConocoPhillips would seem to be the odd man out. But the oil giant took pains to stress that it too is going green, albeit in a very modest way, noting that the company has invested in biomass and lithium ion battery ventures.